first, re: 125 psi, thats on the low side.
second, overall, its a fair price, as long as the MPEM is good, that's critical. (and the shifters are pretty important as well)
duly noted: cables can be pricey, but all the other misc parts at least from my experience are fairly easy to locate and reasonably priced.
I assume this comes with clear title, and trailer ? I'd still like to see you bargain it down a little if you can, getting closer to $1000 will help with taking care of the nickle and dime stuff that WILL crop up.
if you didn't source the DIY seat cover with seadooupholstery.com, check them as well, I had my challenger kit from there and I was extremely pleased with the work.
overall I found the seadoo boats pretty easy to work on, the hull cleaned up nicely with soft scrub and wet sanding, compound and wax, the plastic can be restored, cupholder replacements can be had at wall mart, hatch clips are only like $10 each on ebay (you just need the right part #) used motors tend to scare me,, a new one at SBT isn't that much more and comes with a warranty and its right around the corner from you,
edit: like nick said above, 125 is NOT a selling point, thats a negative.