2/4 Bit Shift Register
have you tried looking in the 74xx series of logic? Pick your favorite flavor. 74HC194 and 74HC195 are 4-bit shift registers; 74HC174 (quad flip-flop) and 74HC175 (hex flip-flop) can be made into shift registers.

edit: based on your comments, why don't you use an HC594 (output) or HC597 (input)? They're 8-bit registers, easily cascadable to arbitrary lengths, compatible with a SPI interface as well as plain old clocking.