If I understand VLRA batteries, they are basically any Sealed Lead-Acid batteries, if thats the case, the following place sells Delkor Royal DC31 100AH batteries -
http://www.nrgtechnologies.co.za/ They go for R1750, I don't think you can get any cheaper.
They are very good performing batteries, used for UPS and Marine, so they are quite robust. They also come with 2 sets of terminals, not sure of the terminology, but the fatter ones for boats and the thinner ones for UPS, so they are quite nice to connect in parallel as you can use each seperate terminal to bridge to the next battery.