Topband: BOG antenna

[elan paim]

hi 
i am looking for some help/ info 
i have a bog antenna 200 meter long and it feed with 50 ohm rg58 coax sir are very good from 160/80/40/all the way to 30Mhz 
i am only using it on 160/80/40m 
however as i can see Bog/beverage have some attenuation on the signal i hear 
i know dx engineering sell some  preamp but the cost is very high for the shipping 
so i like to ask any one what is a preamp i can use ? 
is there any kit recommended ? 
is any one have any preamp for sale that it will fit my rg58 coax ?
thank you kind 
vy 73 elan g0uut