I've got the stock spring off my TE310 you are welcome to. It's off a KYB shock and the WSM says it is 5.2 - 5.8.
No. It lists 5.2 for the TXC, but for some reason on the TE it says "5.2 - 5.8". Not a clue why unless there is just a wider production tolerance for the TE springs.