If your buddy would take pictures of the Apple-applied ID stickers it would be more helpful than anything else in determining what it was when it left Apple's factory, but chances are *really good* it came through Sun Remarketing. And if that's the box it came in it points toward the floppy and hard drive both being Sun upgrades rather than original parts. As noted, a "Lisa II" can be either a Lisa 2/5, which is essentially an upgraded Twiggy-Lisa, or a 2/10. The presence of an internal hard drive points towards it being a 2/10, but Sun's third-party hard drive upgrades could be installed in a 2/5 if you swapped the power supply so it's not definitive evidence of it being the newer hardware rev.

Given the completely INSANE prices old Apple hardware is going for these days I'm in no position to say if $1700 was really getting "ripped off" or not, but... wow. Guess your buddy must have really wanted it but I hope it wasn't for short-term "investment" purposes. The "provenance" of this example just doesn't look to be that good.