FN SPR detachable box magazine question

[Paratrooper501]

I have had a new in box FN SPR A1 w/DBM which I purchased in April 2010 and I just now finally have the money to start building it up. I'm wondering if anyone makes a larger than 4 round DBM for the rifle. I see on the FN website that they make them for the A5 model but only have the mediocre 4 round ones for the A1. Other google searches have returned nothing except finding this sweet website. Thanks for any answers.