There's now a new reproduction of the lenses available, from Vintage Racer, in this FGRV community. From his recent post:
NEW 1984-1986 Uhaul
CT-13 & VT-16 Replacement Tailight Lenses
I have had a project for the last 1 year + to make NEW 1984-1986 Uhaul
CT-13 & VT-16 Replacement Tailight Lenses for those of us with Vintage Uhaul
I now have these lenses available for purchase. The lenses are a direct replacement for you cracked, broken or dingy original tailight lenses. Although not original in appearance (1 color Red) instead of the original 2 color (red/yellow) these lenses are a direct bolt on replacement for your original tailight lenses.
The cost is $79.00 per pair SHIPPED to you in the lower 48 United States of America. Shipment to other locations with actual calculated shipping expenses paid by purchaser.
Please contact me directly at 615 347 7459 if you are interested. Telephone calls only please!
Thanks and MERRY CHRISTMAS!