I have rims from jaguar xj8 , looks like it's from xjr,
original r18 rims , with good universal tires,

i want to place it to ebay.co.uk , but i don't know how much i should ask for these rims , maybe 200 pounds for one rim ? maybe too much?

https://i.imgur.com/zSNcfcMr.jpg
https://i.imgur.com/QsHXWfhr.jpg

 

Depends on condition and the type of wheel?
I would look in The Marketplace and price against what you may find there. Top task bar, 4th prompt over from the left.
Keep in mind it depends on the condition of the rim/tire. Any curb rash automatically knocks about 20-30% off. But if you have them refinished, then add approximately the same to the good side. Tire wear would effect cost since you would like to get at least a little bit for the rubber. Don't forget about shipping, its a bulk item, so it won't be cheap to ship.
Check on eBay also and get an average, be sure of condition for proper analysis. These guys deal in used parts... XJ8-VDP-XJR (98-03) - Body Parts - Page 1 - Jaguar Parts Specialist ...and here also... Car-Part.com--Used Auto Parts Market
You'll obviously have to convert the $ to pounds for a rough estimate.

 

I bought a nice set of four Pentas in the US for $150 USD for the set.

Search "Jaguar Penta" on Ebay to see what people are asking in the UK.

 

I've been looking for a spare 18" Penta alloy on EbayUK, they're running from about £80-£150 as a Buy It Now, depending on condition.

My local JagBreaker will do a full set for around £300, but I only need one.

My Asteroids seem to be double that, which makes getting a spare one difficult.