Service Block Decode

[Macdon221]

some help appreciated. From a 68 service block. It has the riveted blue tag.

I got the S, the 440 and the Water Test....

Can anyone help with the last digits?

 

[Fran Blacker]

To the left of 2 it looks like 118. I enlarged pic 400%.
Edit: Bottom of 1's cut off but can see top and shadow of an 8 on bottom half .

 

[Macdon221]

Yes I agree.

As the spacing is not would normally be on the stamp pad...can anyone help to decode the dates/info they are presenting?