UNC-Charlotte should come in around $30K / year
https://marchingband.uncc.edu/
East Carolina might go a little over but it might be worth a look.
UNC-Pembroke should certainly fit in under your budget
http://www.uncp.edu/academics/colleges-schools-departments/departments/music/ensembles/spirit-carolinas-marching-band/drum-corps-and-uncp-marching-band