I thought I would add some more info to this post. I had mentioned that I bought a solvent trap for a play build, actually I bought two. I was curious as to their construction. I actually was solicited for a solvent trap on Facebook, the company had a Denver address and took Paypal so I gave it a shot. The purchase date was 4/26/20 and the traps arrived from China today (apparently the "warehouse" was out of stock). Total out of pocket including shipping was $78.
First was a monocore. I guess it is 22LR sized. Interestingly enough it was ready to shoot with the two endcaps supplied. Please spare the lecture regarding shooting it, I know. All aluminium, nicely finished, some leftover milling alum. in the monocore, two caps, and a funny straw I guess for the solvent trap to function.
The next was I assume a rifle can, all Al, nice heavy K bafffles undrilled but dimpled, o rings, same nice anodized finish.
I will give it some thought and see which I will efile on.