I can't find anything older than pentium 4's being sold locally (as in, e-waste shops) and not going to pay ebay prices. Got my pentium 166 back from 1998 that I sold to my neighbour. He whacked it in this case though:

It actually lets you use 72 pin edo ram and sdram side by side! It came with 128mb sdram and 2x4mb edo. I got 2x8's from a friend (who thinks they're "rare as rocking horse poo" but he must be thinking of 64's) in it and took the sd's out, underclocked it to 90mhz as I wanted to experience as close to my 386dx-40 first doom experience as possible. Check out that SCSI burner! He lost the card for it though. I didn't need it as I raised $500 for an ide 4x burner which is a pretty good effort for a then-15 y/o, selling computer crap that was even older than what I had (I think a cyrix 686-200 at the time)

Absolute havoc inside:

Does anyone know if moslo 4biz allows you to set a clock rate equivalent to a 386/486? The deluxe version has this.