The price is a shade on the high side but not alot... and if the tires and the pins and hoses are good --- well, you might get 'em down $1,500 - $2,000.
When I decided to sell my JD970, I looked at the deal in parts... The Model 80 FEL was in very good condition and after lookin' thru MachineFinder, etc. I figured it was worth around $2,500 - $2,750. Even a fairly junk 80 is goin' for $2K.
The 8A hoe I had was low hours; maybe 250 total. So, I figured it was worth around $5K. The model 8 is an older hoe but if it's fairly tight (pins), bucket square and teeth, OK, cylinders dry -- and has new hydraulic lines -- I could imagine it bein' worth around $4K.
That's around $6K for the loader and hoe.
What shape is the tractor in? Rubber @ 70-80%; how's the clutch and brakes? Got a good seat? You can put $200 into a new seat... 900 hours is pretty low time for these tractors. The tranny solid? Stays in gear, etc. 4x4 work the way it's supposed to? If the tractor is decent on those items -- you probably shouldn't loose a whole lotta sleep givin' him $6-7K for it --- IMO.
Best of luck in your dealin's.
AKfish