Have a think if you really need a drop forward as they usually make your playing profile worse e.g. push your elbow out wider and hopper higher up, before you spend your money, especially on such a short gun as a DM7.
odd's right, the drop forward would make your profile generally worse i beleive, although if you already play like that or find it more comfortable go ahead with it...
although im not sure where to find one, phone up lips maybe, or use your good old friend google