I have unfortunately punctured the side wall of my trailer tyre on the infamous R355 and now need to find a suitable replacement.

Trailer is a Metalian Mini with a TTT - fully laden is most probably in the 800kg range.
I still have the original Kumho tyres on.

I have the following 2 choices (Without having to get a tyre shop to order in)

Dunlop Track grip

OR

Velocity Raptor

Size 215/80 R15

Both are similarly priced at around R1600

Which would be the better choice in tyre?