Can you get a hold of a bore light? for a look see would be the best thing you could do.
Otherwise that's cheap for a T/C flinter. Its worth a try to bargain it down a little But I wouldn't be disappointed at 200.00 myself.
You might want to check the barrels engraving for the letter K which means it may have been put together from a kit. Is the barrel finish blued or has it been rust browned? Otherwise look carefully at its overall condition nicks, scratches, dents, & cracks in its stock or metal. Bore is the most important of all to check prior to purchasing. If allowed? Take it to a gun shop and have them check its bore if your unable to. Just my opinion is all. Maybe others here have other topics/things to add.
Watch it!!! their both out to get us.