Help Identify A Pen

[Orpilorp]

I need help identifying this pen. It's a button filler and the F nib has '503' written above some writing which I cannot read. The thinly plated clip also has writing that I can't decifer.

 

The pen writes writes very well, comparable to my favorite Sheaffers. Would appreciate it if anyone could help identify.

 

Sorry for the picture quality. Thanks.

[Mech-for-i]

this is probably an early gift pen. The photo quality on the nib is too low for me to read anything, will need a better higher resolution capture. The clip's text though read " 萬夀 " which might or might not be the brand name, but this is a common phrase used to praise for birthday to usually elderly and seniors. The nib embossed imprint though look to me reading the same two text though. The styling and that the characters being full Chinese Text instead of the simplified text used in China today suggests that this is likely a pre war model. The clip and bands used suggest that this is likely very late 30's or early 40's , might be even the immediate after war period. The heart shaped breather hole suggest somewhat up market position also. can the 503 means gold content !?

 

If you can identify the plastic and material used, it might help to date the pen