Hello Jappy & welcome,

Since you're restoring, you "should" be able to find OEM wheels on e-bay or elsewhere with likely OEM tyres fitted, at a reasonable price. You can always negotiate the price down after postage fees & tyre wear are assessed etc etc.

IMO, you're better-off with the standard sized rims & tyres for a number of reasons, not at least being able to get the correct wheel alignment completed.

All the major tyre brands will likely offer a couple of choices at least to fit-up, with typically one tyre being grippier & sports oriented, & the other longer lasting. The amount to choose from is huge if you stick to std sizes & rims.

I like Pirelli myself. They generally offer a better ride & more grip than comparable makes bagged in the same basket, though may wear out a little quicker.

Expect 20-25,000 Miles of tyre life with OEM fitted kit. ( Or if you rather, 30-40,000 km's )

Should you choose to go for over-size rims etc etc, suspension components wear-out-quicker & break, the ride is crap, speedo may be out-of-correctness in readings, & tyre life will be terrible & very expensive in upkeep. Also, in some circumstances, a new higher ratio differential may need to be fitted to restore  the loss-of-power experienced if you've gone too far in rim-size.

However, some would argue that this is still worth doing because the car looks better.