Where to find downtube indexed shifters?

[RunningBehind]

Where can I find clamp on 12 speed downtube indexed shifters?

Right now I have friction shifters mounted on the stemof my 86 Fuji Allegra and I'm looking to upgrade to indexed shifters.

Thanks!

[DaveM]

I don't think these are made anymore. Looks like there's a few sets on ebay for semi-reasonable prices.
I assume you have 6 gears in the rear. So what you are looking for is "6 speed" shifters. If your frame has the posts on the downtube already, you can use ones made to go directly onto them like these:
http://www.ebay.com/itm/SHIMANO-105-SIS-LIGHT-ACTION-BICYCLE-BRAZE-ON-6-SPD-SHIFTERS-SL-1050-/151181997166?pt=US_Shifters&hash=item233326346e

If your frame doesn't have posts, you will need a 'band type' that clamps onto the frame.
http://www.ebay.com/itm/NOS-Shimano-Dura-Ace-SL-7400-SIS-Index-shifter-lever-for-6-speed-down-tube-mount-/380814856289?pt=US_Shifters&hash=item58aa559061

Finally, your freewheel has to match the shifters. So you need a Shimano compatible freewheel to go with Shimano shifters or Suntour->Suntour.

You may be able to go to 7 speed depending on the width of your frame, which might make it slightly easier to find shifters.

You could also think about going to bar-end shifters as another options.

[nfmisso]

Here are 7 speed ones: http://www.amazon.com/SunRace-SLR30-Clamp-On-Shifters-28-6mm/dp/B00D5DQ44A/

They claim 6 speed too, but Shimano 6 speed is 5.5mm center to center, and Shimano 7 speed is 5.0mm center to center - so not likely, but would work with Suntour six speed....
http://sheldonbrown.com/cribsheet-spacing.html