Ducati Sporting Club UK - 900SSD Help Needed !! Any Classic Experts Out There ??

Any classic experts out there that might be able to help/convince me that I'm doing the right thing ?

For some strange reason I've completely fallen for an old Ducati classic, a 900SS Darmah to be exact but I'd like to be sure I'm not buying a lemon !

It's a 1981 UK model with 24,000 km on the clock (km clock rather than mph ??) but the log book and the seller both indicate that it is a bike that was first registered here.

From what I can tell it's almost original : has the Conti pipes, Marzocchi rear shocks,Brembo brakes and I think FPS wheels (seller told me this as couldn't find any markings) plus what appears to be the correct switchgear.

It even has the original wire engine seal underneath to suggest the engine has never been apart and it seems to run as sweet as a nut with no obvious oil leaks or smoke.

Engine & frame numbers I think are within the right range but maybe someone can confirm ??
: Engine 904228 DM860 , Frame DM900SD 950462.

The only things I think are not original are the K&N filters on the carbs and it looks like it's had a respray at some point but the standard looks pretty good and seems to mimic the original paint scheme.

Also, no kick start on it but assume that's correct for this year ?

Does anything stand out to suggest this is or isn't the real deal and what would a bike like this be worth ??

And, assuming it ends up in my garage who should I use for servicing in the South East ?

Oh, and whilst it was running (admittedly only for 5 minutes from cold) the oil light only went out if over about 2500rpm. This sound right ?

Thanks to anyone out there who can help !!