It 'might' work but I wouldn't do it for longer term reliability.
You should be able to use 74HCT93...? I found this:
"LS means Low-power Schottky, one of the many types of TTL (74xx series) logic. This was the less power-hungry but slower descendant of Schottky.
'LS is all but obsolete now, it has been replaced by HCT, a CMOS-based family that is compatible."
Normally I found it to be the other way around, only 74LS** available rather than 74**
Jaycar have them for $2.20:
http://www.jaycar.com.au/productView.asp?ID=ZS5093&keywords=74ls93&form=KEYWORDProbably get them cheaper online though, but Jaycar gets you going in a hurry.
