I have been trying to find some new injectors with a higher flow rate 630cc (or higher) but I cant seem to find any good injectors that are compatable with my model (2003 xjr) do you guys have any recomendations?

 

How many kilometres/miles are showing on the instrument cluster?

What is the issue with the injectors already installed?

Biggest issue is how it's going to pass smog with different injectors.

 

If using a supercharged AJ27, then Avos proved that the OEM (360cc) injectors (can push towards 400cc with higher fuel pressure) and OEM ECU were good to ~ 600 HP using his KenneBell twinscrew solution, so unless you are shooting higher than that, they should not need changing.
If your existing injectors are bad, there are suppliers of remanufactured ones (rockauto etc.) that work fine.
The injectors are a bit unusual I believe - very slight chance that early 2000s Suburu WRX 550cc injectors might be made to work, but I don't know of anybody that has tried (they just look a bit similar in photos....), and then the fuel rail fit, electrical specs, dead times, etc. may well mess up the ECU fueling algorithms even if they did fit.....

 

anything that fits. or 4.2 heads with a red injector set