Hey guys there are significant differences in prices with these parts and not sure if there is a difference in quality ?
Can anyone share some light?

CHeers 

aisin makes the pumps for toyota, so if you get a genuine toyota one it will have both names on it.
 
however, i'm not sure if you can only buy the complete pump and housing from tooyta, whenever i've seen aisin/gmb pumps they are only ever the pump only, so depends if you need the complete housing also.
 
genuine toyota is best, but prices can vary greatly, try road and track for a price as opposed to your local toyota dealer for better prices

I got a complete genuine Toyota water pump from Road and Track for a good price.
I had been told to go for the full pump and not just the front insert, as some aftermarket inserts may not suit your old housing, resulting in a reduced flow.

I rebuilt my engine at 90,000kms and the oridginal toyota / aisin pump was in great condition with no play or corrosion so I didn't even replace it, the factory pump is F&$king tuff!