That lens should have a thread size of 55mm so search for 55mm lens cap and you'll find dozens of results (e.g. Amazon) - any 55mm one will do. Moreover you can 3d print one yourself if you have a 3d-printer. The lens bayonett caps are bit more rare, so for that I'd recommend 3d printing again instead of looking through eBay.
I saw someone call it that but it's basically just varying sized rubber cones that you use to press against the lens ring and unscrew them. Some elements can only be removed by the spanner but most rings (with the logo and info on them) come off in a snap with the rubber cones. Also, you don't run the risk of a spanner slipping and scratching the lens so I defer to the rubber option in most cases.
https://www.amazon.com/Japan-Vacuum-Camera-Opener-Repair/dp/B0013HFYKK
You can try to repair it with neoprene wetsuit repair stuff. It worked for my Kiev 60 with a sunburn hole.
I use those extractors to remove a stripped screw in a smartwatch, I bet that the bigger one can be use for your screw.
If you really want to spruce that dent ip, look into a aluminum blacking pen. They're commonly used in the gun community, but I've been using it for knick and scratch coverup on pretty much anything aluminum and anodized black. Amazon.
Now it's not true black, mostly because it's a chemical oxidation you're creating with it; however, is can be a dark gunmetal gray or a little darker depending on the aluminum. They make the same thing for steel too, if you are working with that instead.
Well there's always this "camera" that has the minolta name, and which you can buy new. Sad place for the brand name to end up
I can give you a partial answer.
The tool for a screw with two holes is called a spanner. You can get them pretty cheaply on Amazon or at other places. (E.g. this item.) Or you can improvise by using, say, two nails and a pair of pliers.
Seals, including the mirror bumper, are easy. If you e-mail Jon Goodman ([email protected]), he'll sell you a properly cut set for your camera and will provide a very good set of instructions. For about $10.
I use the Weincell MRB625 Replacement to get better metering accuracy. One thing to keep in mind is that once these batteries are exposed to air (you have to remove a sticker), they will perpetually "leak" energy and will run out even if you don't use them. Plan to have several in your camera bag and to use the battery check (BC) toggle on the bottom of the camera before each trip.
Any general tripod will have the same thread size as the Minolta. It's generally nice to get a tripod with a detachable head, so you can leave it on the camera and just clip the camera into the tripod without screwing it in every time.
This is barebones but would work: https://www.amazon.com/AmazonBasics-60-Inch-Lightweight-Tripod-Bag/dp/B005KP473Q/ref=sr_1_3?dchild=1&keywords=camera+tripod&qid=1595059257&sr=8-3