Here's an antenna mast you might want to consider.
AB-1386/U NSN: 5895-01-381-6341 quick-erect antenna that raises to a height of 33 feet, much higher than the obsolete OE-254. Check it out at the website below witn NSNs for other attachments and accessories. It is class 9, non-recoverable item so it can be ordered through your motor pool. However, the FEDLOG says it costs $3998.
http://www.armyproperty.com/Equipment-Info/QEAM.htm
A new antenna to put on your mast:
COM201B NSN: 5895-01-498-0332. Class 9, Non recoverable, $2201.82. Attached is a spec-sheet. You can google "COM201B Antenna" for about 31,000 hits.