The S7/V7 should run your Oudie without a problem, the power supply from
the S7 to a PDA is rated at 2 amps.

This is a cut and paste from the LX Nav web site

PDA port input/output on RS232 or TTL level for PDA/PNA devices with 5V
power supply (8 pin RJ 45, 5V output max 2A)

http://www.lxnav.com/products/lxnav-varios/s7.html