Original alloy fenders are almost unobtanium, and priced accordingly. The clip on bars can be had and you'll need the undrilled triple clamp, but those should be relatively common, but probably not cheap. They were used on the early Sherpa S models. A friend has or had one of those bikes. I think he still had it and his MotoGuzzi Ambassador last time I spoke with him. I bought a Metralla from his son back in 1976, my brother now has it in restored condition.
That's going to be a nice ride when you're done with it. If you want to put on a set of fenders that mimic the stock ones in plastic, get a set of the Acerbis trials fenders in red. I have some on my M27 Sherpa T and they look good for the era... cost way less than even one alloy fender.
Feel free to PM me if you have any questions, I have a friend who may be a source of help. Hugh's is probably the best source for some parts, but I have a feeling my friend could set you up with bars and a triple clamp for far less than they'd want. He bought out a bunch of Bultaco inventory here in eastern Ohio. He was a Bul mechanic and has probably a dozen assembled Buls of a wide variety in addition to the parts. I'd have to contact him to get an okay to hook you up if he's willing.
Ever get lost? You know, that good kind of lost - come to a dirt road intersection and you have no idea where you are or which way to turn? I like when that happens!
Mark - klx678
95 KLX650C w/Vulcan piston bigbore, 90 Zephyr 550