A quick test for minimum quantity 2 layer 10cm x 10cm boards shipped to Canada
Itead : $30.16 (10 boards)
Elecrow : $17.84 (5 boards)
As I only need 1 or 2 copies of the board, the number of spares is irrelevant for me.
Elecrow has lead-free HASL for free, Itead is an extra $10.
For a larger 15x20cm board (for your retrocomputer lets say) :
Itead : $96.00 (5 boards)
Elecrow : $76.34 (5 boards)