'96 4x4 16" wheel replacement

hi all - the short version is that a guy lost control of his truck with a small plow on it and my front left wheel met the business end. luckily it was a slow collision and nobody was hurt. i'm seeking help for a few questions - i've been sleuthing with the search button and have gathered some good info but am still not confident to move forward without some input. the truck is a '96 2.7L 4x4 with 16" wheels. to replace the winter tires i'm thinking 225/70/16 or 245/70/16. i dont care about the aesthetics of size or wheel looks.

questions:

1. according to wheel-size.com it doesn't look like 16" wheels happened until the 98 prerunner. if i go to discount tire the first 16" wheel is for a 2001 TRD, but its a 108 bore. i'm having trouble finding something that matches the specs of 16", 6x5.5 lugs, and 106.1mm bore. i'm also not sure what width - 6"? and offset - 8mm? any shoves in the right direction would be appreciated.

2. the door card says that OEM is 225/75/15, or 28.3". am i right to assume that this is the optimal diameter for the speedo/odo?

3. i had a set of 225/65/16 winter tires on, which i know were undersized but was all i could find on craigslist in a pinch. there's a ton of info on the forums about how big you can go with tires (my summer set is 265/70/16) but i'm wondering if it's a bad idea to run small, beyond it looking silly...

4. are there any downsides to running one mismatched wheel, if the lug/bore/offset are correct? would differing wheel weights be an issue?

5. does the wheel look salvageable? i'm a metalworker by trade and it seems like i could fairly easily grind weld and rebuild the contour of the rim - is that a bad idea? i haven't checked yet to see if the wheel still runs true otherwise but am curious if i should just put it in the scrap pile or not.

i know that's a lot all at once - thanks in advance.