Looks like a solid car with plenty of potential. Buy it, get it running, see how bad the engine is. Do all the other stuff necessary to make it a daily driver (as described by sdewolfe) If the engine is bad, a decent running B18 or B20 shouldn't be that hard to come by (or expensive) and is less than a day's work to drop in.

Put the 740T swap on the back burner. While it is by no means impossible to do, (and the resulting car would be a blast to drive if done right) it's far more than 10 days work to do such a conversion. 122 wagons have a 4.56 rear axle, which is WAY too short, especially with an M46 transmission. Start off in second, 0-60 in maybe 6-7 seconds, 4000+ rpm at 70, 15 MPG if you're lucky. You're going to need to swap the rear end. 3.73 or even 3.31 would be a good choice. The stock 122 axle shafts will not stand up to the torque of the B230FT. They are likely to shear off at the outer end, where the keyway for the brake drum is. You will also want to upgrade the brakes, as the finished car will be seriously fast. If you use a 240 rear end, that leaves the fronts. 1800E/ES spindles and hubs will bolt up, have the same bolt pattern as the 240 rear (which the original 122 hubs do not) and can easily use 240 front 4 piston calipers. You will want a dual circuit master cylinder and probably a booster as well.

Just concentrate on getting it going in stock form, and making it safe to drive. If you are familiar with the mechanical work involved, 10 full days of work should be enough to get it all done. Be prepared though, for additional problems to crop up in the first few weeks of driving. They always seem to when reviving a car that has sat unused for a long time.

Or, buy a 240 or 740 that needs a motor, a trans, or something else major you can use from your damaged Turbo.