Are you into sewing?
Here's an idea for making your own.
Notice that the instructions are for a pocket that holds up to 4#, but it can be made larger to fit a 5# weight.
However, you'll notice that the corner gaps are too large for the 1# bags you specified. You might overcome this by adding an additional piece of the 3" webbing under the 2" webbing, so that the ends of the 3" webbing wrap around to create top and bottom flaps. Does that make sense? From the pix it looks like that would close up the corners enough to hold small bags, but you would have to do some calculations or trials to see for sure. I think the stiff 3" webbing would hold the 1 - 2# weights in at the corners, but if it won't you could put a little Velcro on it to hold the 3" flap down, in addition to the buckle.
Actually, if you do that (the 3" flaps) you might be able to replace the 2" webbing with 1" webbing, and, of course, use a 1" Fastex buckle instead of the 2". The 1" buckle is a little cheaper and easier to find (at least from what I've seen. Some of the local fabric stores carry 1" Fastex buckles, whereas I would have to mail-order 2").
Also, I would leave the tail on the 2" webbing loose so that it can be cinched down (the instructions show it sewn down for some reason). If you are worried about the buckle coming off, double-back the free end about 1/2 " and sew it, like they do on backpacks and stuff.
Oh, and use black thread.
UPDATE:
I just did some measurements, and a SeaPearls 5# hard weight is 3 1/2" X 3 3/4" X 1 1/2", so if you made the pocket with 3" flaps like I suggested above, you would have about a 3/8" X 1 1/2" hole in each corner. Probably too big for use with 1# soft weights.
So...
Take the design I linked in and add a 3 1/2 " length of 3" webbing on the inside, to create a small pocket-within-a-pocket? What do you think?
You didn't mention hard- or soft-weights, but I personally want to make some trim pockets that will work with either.