WTB- Driveshaft for Dart Swinger

Based on a conversation with Barracudakid, I ran some measurements. My existing driveshaft (49") just barely slips off of the transmission output shaft, not engaging any splines at all. The yoke is about 7" long, with about 2" at the end not having any splines to engage the transmission. It is also suggested that 1" of play be left on the yoke to account for variations in suspensions geometry throughout the range of motion.

This leaves 4" of splined surface area that is needed on the transmission. If my numbers are correct, I will need a driveshaft that is approximately 52" to 53" long from U-joint center to U-joint center.

Please PM me if you have a drivehshaft within this range. I am looking to start the car next week and would really like to see it move lol.
Thanks again all.

-Mike