Socket 7 will be a Pentium since the Pentium 2 migrated to slot 1. Your motherboard will be an AT form factor and therefore you'd be hard pressed to find another PSU, however hard drives and other such periphirals use the standard 4 pin molex connectors therefore you could just use a spare ATX PSU to power that junk, and use the AT PSU for the board itself.
Those slots are ISA (Industry Standard Architecture) which are 16 bit variants of the newer PCI slot. They obviously have smaller bandwidth but served the same purpose for devices such as modems, sound cards etc.
Intel C2D E6320 / AMD Athlon X2 3800+
Gigabyte 965P DS3 / DFI nF4 Ultra-D
2GB OCZ Gold PC2-6400 / 2GB OCZ Gold PC4000
eVGA 8800GTS 320MB / eVGA 6800GS 256MB
150GB Raptor / 74GB Raptor
2x500GB / 320GB
OCZ GameXStreme 850w / OCZ StealthXStream 600w