Tickford AU2 XR6 VCT Drive belt (again)

[Hannibal1]

My power steering pump chewed itself up, along with tensioners pulleys and belt.
I can get a 6pk 2515 belt which every one seems to agree is the correct one, but it's a very tight fit, and I will have to use some force to make it fit.There is a 6pk 2530 available, meant for a Mercedes (says Repco). Is the 2515 the go or the 2530. Seems a lot of us have the same trouble, so I'm looking for something concrete to go on, Repco is next to useless on this.

Thanks in advance.
Bobc.