If you want different wheels to those listed below, you need pcd converting wheel-spacers like Hubcentric Wheel Adaptors. as 4x100pcd is already relatively common.
What you need is simple wheel spacers in 4x100pcd, centre bore 56.6 to make the offset a little more common. These spacers would fit Vauxhall Corsa, Astra F&G, Tigra, Vectra + OPEL Ascona and are therefore pretty easy to come by and quite cheap. example of cheap spacers
Lotus AWI 5-Spoke
Front
Rear
S1 5 Spoke OEM Wheels
OEM S1 wheels.
Lotus Part Numbers:
Front: A111G0004F
Rear: A111G0005F
5.5J x 15
Size
7.0J x 16
ET14
Offset
ET16
95.25
PCD
95.25
?
Center Bore
?
7.10kg
Weight
8.80kg
185/55R15 195/50R15
Tyre size
205/50ZR16 225/45ZR16
Price
complete set inc VAT ???
Web
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Lotus OZ 6-Spokes (111s, JPS, Type '49')
Front
Rear
S1 OEM Wheel
OEM S1 wheels.
111s are black. JPS and Type '49' are gold
Lotus Part Numbers:
Front: A111G0013F (111s), A111G0029F (JPS, Type 49)
Rear: A111G0012F (111s), A111G0031F (JPS, Type 49)