any intrest in dry base rock?

[i have crabs]

i need some rock to do the back wall of my 300g so i ordered 50lbs from bulkreef supply to check it out, its really quite nice rock problem is i didnt really ask for sizes or anything so i got mosty large chunks that would be a shame to cut to pieces, anyway bulkreef is having a sale on rock so im thinking about buying 150-200lbs but since i have to cut it up some pieces wont be anygood to me and im shure ill have alot of extra rock i wont need,
so if i do order this pile of rock is anyone intrested in the rock i dont use? ill sell it for what it costs me which will be in the $3.50-$4.00/lb range by the time you add the exchange/tax/shipping, i want to order by thursday night to make shure it ships on friday and i dont wanta drop $800 on rock if im gonna end up with 50-100 extra pounds