What's up with figs 3b and 4b in the MM5450 datasheet? Seems like some pin names are missing.
Anyway, since you have (5+7)*5=60 LEDs, you should be able to divide that up into 2 groups of 30, connect those two groups in parallel and to 30 of the output pins of the 5450, and use 2 of the output bits to duplex between the 2 groups as is done in Fig. 13.
Edit:
I just noticed that the transistor in the upper right corner of Fig. 13 is shown as an NPN. It should be a PNP, like the other one.