How much would i get for.....
 

17inch bulbs (and another pack) and a coral life 20" fixture

if you have 17" bulbs i think your fixture is about 20" long. only t5 fixture that is avaliable is the current usa fixture which you don't have to many choice for bulbs but the current usa ones

ok so I couldn't get them anywhere else?

How much would i get for the bulbs and another pack of them and the coral like fixture

That depends if anyone has a need for this size. Being as that is not a common T5 size and replacement choices are limited the market is probably small but individual need may set a higher price.

Mk thxs

also would a 24" fixture fit?

Not sure what you mean but another option is to dismantle the fixture and use the ballast (if it's rated for your wattage), reflectors and sockets and do a retro fit in a home made light canopy to suit bulb length.

Is this stuff new? Can you take it back to the store?

well there's a pack of lights that go in the fixture that are brand new still i package, also are you saying I could just put T5 lighting in my coral life fixture?

I was assuming the coralife fixture was a T5, if it's a PC light then no they aren't interchangable. Sorry for the confusion.