OK i've not got a clue and been trying to find out online and got no further at all. Annoying me now!!!

Anyway they catch on my civic EG (4x114 hub swap) at the rear on the outer side of the tyre.

They measure across if I put a tape measure inside from face to face at what I'm pretty sure to be 8".

They're 114.3 fitment and 15".

Here's the pics:

 

Usually there's a stamp in the back of the wheel near the lug nut holes are or near the lip. Look around on the inside and you should see something like 15x7J or 72.

 

Unfortunately not mate.

After a search around on the net I've found that Ray's dont make things that easy for you and instead put it on a sticker inside of the wheel but this has long gone...

 

You're right...Ray's don't stamp them but puts a sticker. Sounds like you did the best that you could in measuring the width. Here's a link that I found that could help you find the offset. Good luck!

https://www.rsracing.com/tech-wheel.html

 

Most likely it's a 15x7" wheel.

 

Are you sure there isn't a stamp somewhere?

Typically TE-37's have this style stamp somewhere on the hub-side of the wheel: