ah64:

By the way you say it, I assume you're going to attach track blocks to the outside of your 'chain' to make the track, right? In looking at pictures of the T-27, it seems to have that central single disk-sprocket, with dual guide horns on the inside surface. The only problem I see there is that with only one central attachment point, the track blocks will have a tendancy to rotate on that point. One way to solve that would be a strip thin fabric to either side of the main attachment point to prevent this.

If you could find a close batch in a separate-link tracked vehicle it migfht be easier, as most tracks have at least two connection points (usually either end) and often have central holes that could be used for the sprocket teeth.

Only other option I see is having matching links cast, and that is not a cheap option.

I guess it becomes a matter of how accurate you wish it to be vs how much you want to invest in its construction.