Here's a little friendly dad advice on the tire situation. First, there are two places to confirm the tire size. The obvious one is just to read it off the tire you're replacing (which I'm guessing is what you did). If it worked before, then replacing it with the exact same size should reasonably work, you'd think. But the other place to check is on the sticker inside your driver's door jamb. That'll tell you what wheels and tires originally came on the vehicle. When dealing with a second/third-hand car, it's always worth just double checking that you still have the correctly sized tires. If the sticker matches what's on all four wheels of your car currently, you're golden. If it doesn't, then you should do a little more digging to make sure that whatever wheel/tire changes a previous owner did actually are ok. The reason I bring this up is I've seen all kinds of whacky where someone put a mismatched tire on an old beater because it's all they had and then an owner or two down the road that isn't all that familiar with tires goes and puts on a same size replacement when they could have corrected the problem. I even helped a girl one time who couldn't figure out why her tire had burst when it had clearly been rubbing for a long time due to improper/not-original size. So it's always a good idea to just do a little double check. If you discover anything that doesn't match original, go ask about it in one of the car subreddits to see if it is a suitable substitute.

As for a replacement, there are a ton of used tires listed on FB Marketplace in that size. If you can't stumble onto one here or at a nearby used tire shop, you can get one fairly cheap on FBM. Key there is to really check condition. You buy it, get it put on, and it has a not-so-slow leak, it hasn't really helped you out much. Plus if it's very old, it won't have great traction, especially in rain, so could be a safety hazard. Manufacture dates on tires are expressed in a 4 digit code on the sidewall. Those 4 digits are the week of the year, and the last two digits of the year. So a 2224 code would be the 22nd week of 2024. Not worth putting on a 5+ year old used tire even if it still has what appears to be decent tread. Ideally, you'd put on a near-matching tire, like same brand/model of tire as what's on the opposite wheel (like if front right is the flat, at least try to match the other front tire if possible). But hey, cheap is sometimes the only criteria and if it gets ya down the road, I understand.

Last quick tip on tire sizes, the three numbers you list are pretty standard. First number is the width of the tire in mm, second number is called aspect ratio and it's the height of the sidewall as expressed as a percent of the width of the tire (dumb, I know), and the third number is the diameter in inches of the wheel. Those really only become important if you start trying to change something from original or find you have something other than original. But if that helps you understand what you need, it's better than just viewing 215/55/16 as completely meaningless goblety-gook. The R stuck in there is radial, but that's almost meaningless at this point because they are all radials unless you're buying like an antique, OEM correct bias-ply to restore a vintage museum car. And there are some high performance variants like ZR, too, or LT for light trucks. But generally on passenger cars you just need to watch the three numbers.

I've got a crazy busy week or I'd grab my hydraulic jack and impact and get you squared up at a used tire shop. But hope this helps.