Some things to consider.. are they brother and sister? do you trust him enough to believe they are possible het. ghost? Also they are both possible het so if one is and the other isn't, it will take you a while to find out if either or them are het ghost.
Then again, that is a decent price for what i would say are two very good looking pastels, so in the end its up to you. I just wouldn't bank on the idea of getting POGs out of it. Also if they are brother and sister I don't think you can breed them (with good results anyway).
Edit: also keep in mind breeding size pastel females usually go for at least $500-$650. (From what i've seen lately anyway)