Dundee1000 is an agent for BProjects, so if you're in Australia I'm sure he can help. Seriously, I've always thought you could straighten the pushrods, at least close enough to be usable. I've seen people straighten axles, so a pushrod should be fixable, as long as it's not hollow. I'd put it between 2 points & rotate it to measure how bent it is, then using a press, push down on the high side. I'd try a drill press with a block of aluminium in the chuck & something to support the pushrod. using the drill press should make the force so small that it wont damage the pushrod. I'd try & get the pushrod as straight as possible, but not get too perfect. BUT, I'd only do this if it was a street motor. If it was for a race motor I'd go to a Nissan dealer & get a new pushrod, which are the same for an A15 as the A14.
PS the guy who straightened the axle for me was a certified(able) jet mechanic & he used to straighten the shafts on the jet engines all the time. With the axle he took a light skim on the axle face after the straightened it, so the drum was square to the axle. Saved me from trying to find a late 1200 ute axle.