If you have an 8" rim with a 36 offset you will get away with a 225 45 15 at standard ride height. If you go lower you may have to trim the arch liners.
15" tyres are no longer a popular size so in no way expect a full set of size options especially in no motorsport tyres.
Most wide rims are also lower offset and so you can’t get wide tyres to fit under arches.
You should get a 205 50 on that. Be aware there are not a lot of tyres available in that size and you should avoid the Chinese budget ones. The Yoko 701 would be the standout one, but anything decent in tot cheap and you would be looking around £450 for a set.
Your offset puts your tyres too far out from the car to clear the arches with wide tyres. You might get away with a 215 45 15, however I only know of one tyre available in that size
and you are back to paying over £400 for what would be a very mediocre tyre. 225 would be way too wide, needing you to roll and possibly pull the arches and you are into motorsport tyres. I can supply you one, but you are looking at over £170 per tyre.
This is what they look like on an 8" rim.
You have a lot more arch clearance on a MK2 and these are lower offset too.