We have opportunity to buy Hewlett Packard HP 75A (HP 92275A) toner cartridges dirt-cheap. The problem is: The HP 75A is compatible with a LaserJet IIIp. We have the discontinued model LaserJet III, and retailer specifications of the HP 75A cartridge omit mentioning our [obsolete] LaserJet III as an accepting printer. The question is, can we actually use the HP 75A on our old Laserjet III printers even though there are no acknowledgements of the fact, or is the HP 75A really truly unusable on our HPIII’s?