Vintage Blue / Black Enamelware Roasting Pan

Base dimensions are as follows
The base midsection length with 1 handle missing is about 17 3/4" and without the handle is around 17"
The base midsection width is near 11 1/4" and the base height is approximately 4 1/4"
Lid dimensions are as follows
The lid midsection length with handles is about 18 1/2" and without handles is around 17 1/8"
The lid midsection width is near 11 3/4" and the lid height is approximately 4 1/4"
Base and Lid dimensions are as follows
The base and lid midsection length with 1 handle missing is about 18 1/2" and without the handle is around 17"
The base and lid midsection width is near 10 3/4" and the base and lid height is approximately 8 1/4"
One of the handles is missing broken off. When I fit these together, I have to push in on the side to get the smaller lid to fit on top of the base. Do you think these are a set or 2 pieces not part of the same set? Thank you for assistance in this request.
Rob

 

Wonder if this is not a double boiler, missing a lid. Does the top piece fit into the bottom the other way around?

 

I tried but it looks to me like the top piece fits over top the bottom piece and not the other way around. Also, the top piece has the outlines of letters but I can only figure out that it has an i in it. Rob

 

Possibly LISK? It's an oval roaster. The two pieces may be meant to go together but the fit is compromised due to denting or misshaping.

A LISK oval roaster:

 

At first looks, that is what I thought when I researched it but mine does not have LISK embossed in middle and mine does not have white specks. Thank you for trying really appreciate your efforts. There are no letters inside the encircled oval ring on mine that is blank. There are like 10-12 missing letters on the other piece. I know it is unreadable from the picture and it is unreadable when I was looking at it at different angles in the light as follows:

 

These were being reproduced in the 80s. I have my mother's original roasters in different sizes. I had bought my own new and it was poorly made. Hers are still useful.