7805 vs. 78L05 voltage regulators
Yes, you should be able to substitute a 7805 for the 78L05 if you are willing to do a little kludging mechanically.  The L version is physically smaller and can dissipate less power and may be rated for less current.  If this is just a one-off, go ahead and solder on a 7805 in a TO-220 package onto the pads intended for the 78L05.

By the way, that must be a very old design.  10 nF is rather skimpy for the the input and output caps.  Nowadays you can easily put a small 10 &micro;F cap on the output, and at least a 1 &micro;F on the input depending on what the input voltage is.