Half-long pipes (plurale tantum)
Bagpipe, bellows-blown: 2 stocks (a: single chanter / b: 3 drones in 1 stock)
Bellows-blown; In Marcuse and Podnos spelt "Half long pipe" [singular, without hyphen]; NB (plurale tantum): The term is also used when referring to 1 instrument only.
Baines, Anthony: Bagpipes [1960]. Oxford, 1973 (revised), p.117.
Marcuse, Sibyl: Musical instruments: a comprehensive dictionary. New York, 1975 (»Baines; »Grove, 5th ed.).
Podnos, Theodor H.: Bagpipes and tunings. Detroit, 1974, p.18 (»Baines; »Cocks (Grove)).