check out this unregulated power supply

A worthy candidate for MBSID? I already built the c64 optimized PSU, but always looking for a modern solution:

http://www.paia.com/proddetail.asp?prod=K114&cat=50

That is basically just the start of a bipolar power supply, which makes sense since that is part of the PAiA kit stuff and bipolar supplies seem to be common in analog synths. It’s super basic - you still need to regulate the voltage down to what you need (+5V and +9 or +12V depending on your SIDs) as well as the extra filtering caps. Basically if you’re going to go that far, might as well go all the way. I don’t know what your design plans are though so not knowing that makes it hard to suggest a specific PSU options (of which there are many).

http://discourse.midibox.org/t/topic/15037

And actually you probably can get away with a wall-wart in most cases unless you’re going with something fairly fancy (external filters, fully stuffed MB-6582, custom chassis, etc.).