I'm like a bad penny that way. I even refrained from rubbing salt in the wounds telling you "I told you so" about selling the manual stuff I sold you! I'm pretty sure you've already kicked yourself in the ass for that so I'll leave it there.
If you can't find anything locally to you, the guy that did mine could probably build and ship one your way. Or you just come to Denver to pick it up. The place is :
Steve's Transmissions & Gears
2220 S Lipan St, Denver, CO 80223
(303) 744-7904
His 4500 builds eliminate the stock fiber synchros and usually has both the early and late styles and like he did on mine he can set it up with the low ratio first gear with the later unit with the better shifter and integrated slave/release bearing. The low gear choice has pros and cons either way, but I wanted all the gearing to work with my 241 and 4.10 gears. With the 8.1 torque I never use 1st on the street with either ratio, but I wanted as deep as I could get without the expense of a doubler or Magnum. But given the weight of a camper-equipped K5 and an LS small block you might want the higher 1st gear ratio to help the lower torque (at lower rpm) engine on the road.