hi,

For columns, i have 8 74LS164 (i.e for 64 columns)

Wow! So max. 64x35~=2,3A should be provided by row transistor.

I have gotten LS138 for row addressing. i will use TIP32 (to allow for expansionof the columns later) as the buffer in place of the TIP125 (not available)

As it has been already mentioned, 2,3A requires very good control.
You see, TIP32 has typical h_FE=10 only. It means that the base current of TIP32 must be at least 2,3/10=230mA. LS138 cannot produce such current through its outputs!
In such case, I suggest you to use two transistors: the first transistor (connected to LS138 output) may not be power one but it must have the big h_FE - it is used as pre-gain transistor.
And the second transistor as power key.

Regards,
Oleg