Best guess is to consult the Home Office MSS at the National Archives at Kew (it may be worth searching through Series HO 42, which is partly online, and includes the domestic correspondence between Lords Lieutenant etc and the Home Secretary -- there may be some information there). Otherwise, what you need is probably either in the Supplementary Correspondence regarding the Volunteers, 1794-1813 (HO 50/330-356) or in the Volunteer Establishment Books at HO 51/108-9 (although this only covers 1802-3).

This may of course not be helpful, if you're not able to get to Kew easily, but it's the best I can think of!

Best wishes

Jacqueline