Dell TrueMobile 1184 Router. Need Repeater.

A client has a "Dell TrueMobile 1184" router in her apartment. She has
a terrace but does not use the internet from the terrace. It is about
100 feet outside her network range and I suggested a repeater. She
asked me to buy one for her and set it up. I ordered a D-Link repeater
but it was incompatible with the Dell router. We returned it. My next
visit will be a follow-up, so I am being extra careful this time which
repeater we get. I emailed Dell wireless support who recommended a
repeater from a vendor called Buffalo, however, I emailed Buffalo and
they said the repeater was not compatible with the Dell 1184
TrueMobile router. Doh! I've been looking but cannot find a repeater
known to extend the network range from a Dell 1184 TrueMobile router.
The repeater needs to extend the network from 328 feet, which it is
now, to about 450 and I'm hoping, if there is one, the repeater will
cost around $80.