Crantius

Hofi uses Sikaflex 11FC because that's what he could get at the time when he started using it in Israel. This stuff is not a glue, but a sealant. It typically costs <7€/cartridge. If you can find a high strength polyurethane sealant that has a shore hardness of 37 or higher, break elongation ~700% and is marketed as elastic or vibration dampening, chances are it will work similarly well.

The body of this hammer is round, so a large knife vise should work for rotating it evenly.

pump spray bottle. especially nice to use the mist setting on myself when temps are risen (outdoors smithy).

Looks like a spatha. A sword popular with the Romans and later the Vikings (i.e. early dark ages as you said).

They might make decent guillotine tools if they're thick enough. Probably some kind of high vanadium abrasion resistant stuff that is difficult to heat treat and doesn't hold a fine edge, idk ask the manufacturer.

Outstanding work. How was the wax (?) form of the cast shape (the one you're holding) made?

Taps/dies: remove rust, keep, especially the large ones. Make guillotine tool inserts from dies if you really don't need them.

They look like hot cuts. The one in the middle might be a sort of punch, i.e. a tool that is used to make a small hole which can then be widened by a drift. If they have flat or radiused tops instead of an edge then they were most likely used to sharpen scythes.

bear

third post in this very forum

2€ per kg (2.91AUD) is considered a reasonable price here in Germany. Although we're seeing more and more ridiculous offers lately (ebay and similars), probably private sellers who've seen other overpriced anvils and advertised their own for just a little bit more.

Forge in red/orange temp range, not above or below (unless you're using mild steel, then it doesn't matter). Anneal or normalize before hardening. Use heated oil to quench, or brine.

Copper and its alloys will braze to steel. Even with alu it's a bad idea, some of it will oxidize (% depending on the type of scrap you used) and prevent the rest from melting easily, i.e. that crucible will be ruined. Copper also oxidizes easily, it needs a topping of glass or coal to reduce losses.

What about shapes - is square typically cheaper than round/hexagonal? Can I expect there to be an avg per pound price or is there a premium on larger diameters at same weight?

I was thinking about this area (not sure if I got the proportions right): you'd cut out this section, add inserts (like with this design https://youtu.be/7SCbkeJzj1U?t=15s) and two plates for front/back, welded or bolted to the main body.

I don't see why you want to reshape the other end, I'd leave it as it is, for pieces that are too large for the anvil shaped end. On the other hand you could grind some fuller shapes into that midsection between the usable areas. Or even a rectangular cutout for an integrated guillotine. That would really be something you don't see every day.

You could try carving (similar to this: https://www.youtube.com/watch?v=Df1xPTgLYj4) instead of milling. Try filling the gaps with a mix of epoxy and sawdust or brass shavings. Btw if you have to use some treatment involving heat on the handle, protect the blade by wrapping it in a soaked towel.

Does your RR track anvil already have a (pritchel) hole? Assuming you'll be going to make your bottom tools yourself you can put indexing tabs that go over the sides of the anvil on them, no need for a square hole. Another option would be a hybrid hole with a square taper at the top - some peddinghaus anvils have those along with a smaller pritchel hole. Otherwise go with what Frosty said. It's just a RR anvil... you'll probably want to get something better in time. Here's a thread on the topic: http://www.iforgeiron.com/topic/41257-square-hardy-in-round-anvil-hole/