^What he said works if you begin with a triple crank but are willing to ride with a double for actual gearing. I happen to have most of a T/A tandem triple crankset; no BBs but the right side rear triple and two left syncronizing front and rear crankarms with small rings. What is missing is the right front bare arm, but you could use almost any RH crankarm if you don't mind how it looks. Functionally, there might be an issue with the Q factor since your bike's stays might splay more to clear the 26" rear wheel than this crank was designed to work with.
All this is from memory. My stuff is stashed in the garage and my not have seen the light of day since we moved here five years ago.