I have never owned or serviced a Philco 53-1350. But I do have an original Philco Service bulletin for it (#PR-2422) and I took a look at both the schematic and parts list. These caps do not appear there and I am going to have to agree with Dave on this; I suspect these are not original and were added by someone at some point for reasons unknown to me. The fact that they are oil-filled caps with 600v rating would seem to confirm this. I would also repeat Dave's question: just where do they connect in the circuit?EDIT
: Sean, you apparently already have the SAMS Photofact for the 53-1350 which should be adequate. But if you also want a copy of the genuine Philco Service bulletin for it (#PR-2422) I suggest you contact Chuck Schwark:http://www.philcorepairbench.com/schematics.htm
I realize that Chuck only advertises genuine Philco service data for models through 1947, but I know for a fact that he has a lot of later ones since I myself have sent him
several original copies in the past. But since he is not complete
on Philco data past 1947 that is the reason he does not advertise it.
I am sure Chuck can probably help you, but if not let me know via PM and I could send you a Xerox copy via USMail. But try Chuck first.