Quote:
...even though it is defined better than my other Type I I have.
Oops! Sleepy me read that as Type II. disi, thank you for contributing something that is actually relevant.
Your first one is what you think that it is, a type I #499. There are no other possible variants although single line watermarks can be very difficult to see. As you noted, it hasn't aged well and is discolored.
Your second suspect is also a Type I. Some of them have a pretty well defined top toga rope line and button outline. Your stamp does not.
As penance for posting when I'm too tired, here's a variant of Type I that can get confusing, the Type I rotary print coils:

Some of these can be difficult to distinguish from Type II stamps until you learn the differences well. This Type I stamp's lines are about as defined as some lighter printed Type II stamps. For these coils you also have to look at other areas to make the distinction.