Wow. I use to have that very same bike in the same colors in the late 1990's, and put many a mile on it. This sure brings back memories.
Mine came with a Zoom Titanium stem and bars, and Shimano LX drivetrain, wheels, cranks and LX shifter/brake levers. The bike was sold at Reed's Sport Shop in San Jose, California, USA for US$2000 (frame only - $1200).
The left chainstay on my Mongoose broke near the dropout in '98, and, unable to find a replacement swingarm, I eventually tossed the frame in 2001. I sure regret that move now.
I ended up on a mid-90's hardtail Schwinn S95.2 frame, and am still riding it today (Go Retro!). Just about everything on it is from the mid to late 90's except for the new seat, tires and model-year-2000 Manitou fork (XT, XTR, Raceface, Kore, Salsa, Chris King).
I DO still have the wedge-clamp type Zoom titanium stem from the Mongoose though, made for a threaded 1-1/8 steerer tube, although the black rubber plug that went on top of the stem has been missing for years...
I think I still have the original 1-1/8 threaded AHEAD headset for it too, stored in a zip-lock baggy somewhere. I'll have to do some digging...
(P.S....your bike looks great!)