For years i kept mine in the closet stored safely, one in good shape, one with a broken ear, but no more! I want to enjoy life. I just recently plastexed mine back together and if they crack more i'll repair em again. Just looks so much cleaner now.
If anyone has a decent fiberglass shop these could be reproduced i imagine, though yeah the prices would be nuts for such a small part...
I'm with capn on the voltmeter though, with modern regrec bypassing the melty red connector going straight to it's own fuse and the battery, soldered stator leads, just ignore it. You can also mount one of the trick single LED meters if you want, i've also got one i've been meaning to install but I just haven't gotten around to it. https://gammatronixltd.com/ There's one mode where you tell it to be stealthy/off under healthy voltage so you'll only see the light when it's over/under preferred range so i won't have to shut it off to keep it from bugging you.
I would really like to sneak in a tiny fuel gauge, something surface mount on top of a side panel for peace of mind. I can't seem to find any era appropriate looking ones though, or anything not huge and ugly. I found a tiny LED bar one that works on bikes with measurable hydrostatic pressure, but it won't work with our weird deep tanks that require pumps, i already asked if it would work with a float gauge(which we could get from 88/89 model and replace our low sensor) but it is not compatible. https://www.lskelectronics.com/store/FuelGaugePro-Bar-Graph-Display-Panel-Kit-p286787313
I just recently redid the carbs on my 700 and used the guide from Joe over at v4dreams and it worked a treat, such a great resource. All the tips i needed, though i did take a ton of pics of the my own from all angles just to make sure I wasn't messing anything up. http://v4dreams.com/maintenance.html
I also read stuff bookmarked from magna forums that seems to work well for me: http://v4musclebike.com/articles/magnandy/Andy's Carb Cleaning Guide.pdf
Setting the bench sync was easiest for me with a 1/8" wide strip of paper(found that tip on some random forum post), dragging that under the throttle plate on the nonadjustable one first and setting the idle screw, the setting the other 3 to match using the linkage adjusters. On the bike at first start the thing was super close right off the bat, barely needed any tweaking to get about perfect per the MotionPro Sync Pro tool i've got.
I installed the metal fuel joints from vinscoottubes on ebay while I was at it, no more worrying about the plastic joints and old o rings. https://www.ebay.com/str/vinscoottubes