About 152lbs for the bare mast if it is an Isomat NG-46. Add spreaders, spreader castings, masthead and forestay castings and fittings, standing rigging, turnbuckles, running rigging, gooseneck, etc. etc. In total, maybe 300-350lbs?
Who's lifting you boat? and do they lift boats very often? I can see asking a about your boat weight, because some boats weigh double of others of a similar length, but masts for a boat of a given weight don't vary too much.
Cheers
Chris