I haven't looked at OP's merit-giving history, but your suggestion is generally a good one.  Merit sources probably shouldn't be handing out merits willy-nilly and should have fairly high standards.  Then again, Theymos did want sources to give merits to posts that are just "good", especially if they're made by newbies.  That was in a PM he sent last September if I'm not mistaken.

Anyway, asking for more sMerits if you're a source is OK in my book.  I had to do it myself a while back, because I was chronically short and didn't even have any earned sMerits left at the end of each month.  It's a good thing that OP is searching for good posts, even if it's just for the purpose of giving merits to them.  He obviously feels a sense of responsibility as a merit source, and that's a good thing.