Hi there. I had a look for David Boast but couldn't find him from a quick look-through. However, some of the muster rolls were difficult to read and I had to guess at names. Also, I've had to miss some out that were completely illegible. The men I've listed didn't get promoted up until about 1846 so I'll have another look later at sergeants. The nearest is Francis Boast but he died in 1841 so it couldn't be him that you're looking for. I'll take a look at the links you've provided as I know I'll find them really interesting and thanks for posting them.
Private 1032 Francis Boyd [Boast] Spent time in hospital, died 1841 aged 23
Private 1112 David Booker Spent time in hospital, volunteered 31st Foot 1844
Private 1301 David Bright Spent time in hospital, volunteered 28th Foot 1844
Private David Brook Enlisted 1827
Private David Byers Spent time in hospital
Cheers
Diana