No idea where to get one locally. It’s surprising that your internal antenna won’t work even flush-mounted. I’ve read where lots of people have them flush mounted in full-sized cc’s with tops and they work fine.
The last couple times I have bought electronics from Jim at BOE Marine, they have gotten to me the next day. He could also tell you exactly what you need and how to set it up if you give him a call.
866.735.5926
I talked to him briefly about adding a fuel flow sensor to my HDS, and from what I understand, you have to build a network (you have already realized this it seems). It isn’t like the older lowrances that sort of came with a network hub to plug stuff into.
Anyway, the LEI extras website has the network components as a kit for like $75, and Jim at BOE can sell you the same thing that may be garmin or lowrance brand (doesn’t matter) for about the same cost.
I am kind of holding off on a fuel flow sensor since the sensor would be 65 and the network would be 70. I can burn a little more gas in my single engine boat for that much more money. I’d like to see some pictures of what the “network” consists of if you get one. I know what it is on paper, but I’d like to see what they’re selling for 70 bucks.
This is what Jim at BOE said I needed for a NMEA 2000 network for a fuel flow sensor (and your external antenna).
$73.55
010-11076-00 - GARMIN NMEA 2000 BACKBONE CABLE (2M) $17.89
010-11076-03 - GARMIN NMEA 2000 BACKBONE / DROP CABLE (1FT) $13.25
010-11079-00 - GARMIN NMEA 2000 POWER CABLE $13.23
010-11078-00 - GARMIN NMEA 2000 T CONNECTOR $14.30
010-11081-00 - GARMIN NMEA 2000 TERMINATOR, FEMALE $7.44
010-11080-00 - GARMIN NMEA 2000 TERMINATOR, MALE $7.44 </font id=“size1”>
Or you can buy directly from Lowrance:
http://www.lei-extras.com/store/search.asp?SearchType=ProdNum&ProdNum=124-69
Part # 124-69 $73.95
Network starter kit. Includes
2 terminating resistors (TR-120M-RD, TR-120F-RD),
two T-connectors (N2K-T-RD)