Hi mate,
Not exactly sure on the price but the homelite trimmers are cheap machines from Bunnings. An all too familiar story. Last time I looked they only cost around $90 brand new. For my money not worth it. If it was seized you'll likely find significant scoring in the bore and piston.
I'd be grabbing parts off it - carby, HT lead, trimmer head, kill switch and binning the rest.
Kill switches come in handy for old daily driver mowers to just hook up an off switch if the normal kill switch is faulty.
Pete