Trust me.. if anyone knows I'd be one of them.
I have two in my garage right now and one of them is now fuel injected. It's actually being converted from an EK32 to an EK33 including jugs, +1mm Wiesco pistons and reed cages.
Search Fuel injected Subaru 360.
Even still, if it's just a front end, floor pan, and powerplant it's still not worth much..
If you are looking for a real price.. assuming the engine is complete and ran not too long ago, Rack is functional, brake cyl's are serviceable by either honing or sleeving.....
Ah, I'm not gonna nitpick.
Basically, A pile of untested 360 parts is worth to a serious 360 collector no more than $200-$350 and that range is based on condition and rarity.
You can buy a mostly complete parts sedan ranging anywhere from $200-$400
If he were selling rare parts like Truck/Van Windshields, Indicator Lenses, Hubcaps, AM Radio insert, Roof Gaskets or NOS pistons.. then he'd have market cornered and could command those numbers.
There are two markets.. The reasonable prices you pay within the club, and the 'You can't find this anywhere!' street prices.
$900 for this sale is well above both.