The TA04 and 414 front belt are the same (low friction version is P/N 53463). The rear belt for the 414 is specific to the 414 only, P/N 6244004. As for the tensioner, I believe it was just two of the flanged steering bearings or 1 flanged bearing and a washer screwed into a standard plastic steering servo mount. To "adjust" tension, you add washers under the plastic piece to raise.
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