Well, if you wanted to piece it together:
Sanyo 4912: $180
2 perlicks @ $35 ea: $70
New 5 lb CO2 tank and regulator: $100-120 (Cheaper used)
Hoses, fittings, etc: $20-30
So it's about $400 worth of stuff (new). So you're paying $50-ish for the DIY stuff that was done, and getting used equipment.
If you're a good DIY'er and bargain hunter, prolly not a great deal. If you want a turnkey solution, not bad.