Well i have no leftover block... DTEK block aint too expensive, looks good, and buying a GPU block would be OK for the cooling but at the same price i'd lose the easy mounting and the 'sandwich' option (one HD over, one HD under) since i've 2 ultra SCSI disks to cool down.
Oh and DTEK customer support replied me in a few hours, and provided all the info i needed. And they have Tygon
yumm