Quick question, anyone know the length of the spring in the front driveshaft on a TRX300FW?

I got one here that the front driveshaft isn't sitting far enough forward on, it was working fine then suddenly the driveshaft started clicking on the diff input, looked and i could see gear lube dripping down from the rear of the diff and it turns out its because the driveshaft had slid backwards and wasn't fully engaging the front diff anymore, splines look ok, it only clicked for a few minutes to get it back to the shop at really slow speed and it didn't click all the time.

The only thing i can think of is the spring is bad, i don't want to tear apart my 4x4 to compare parts, just too much work, so trying to find out if there is a measurement on this spring or if anyone knows if the end when placed inside the driveshaft coupler should be flush with the end of the spring? Its inset about a half inch or so, seems to me its too far in and not putting enough forward pressure on the driveshaft to stay engaged?

I did check the frame, i have heard of things like the frame bending causing the shaft to disengage, but everything looks great, no rust, no broken welds, nothing bent, everything straight and like it should be, so the spring is my last guess at this point and it doesn't appear to be available anywhere as a replacement part??