I am playing this cool game called Territory Idle. In this game, two types of buildings can earn resources. Some earn a resource for each worker while others add one per worker of the resource.
Here is an example: I have two temples, each with 70 workers. Each temple worker earns me 1 faith point plus as many points as there are workers in the cathedral.

I would like to know what combinations of $x$ (the total number of temple workers) and $y$ (the number of cathedral workers) amount to a rate of earning that is a multiple of 1000. For instance, with $140$ temple workers, $49$ cathedral workers give $+7000$ faith per second.
So far I have $x(y+1) \pmod{1000} = 0$
I don't even know if I'm on the right track.
Update:
Using @InterstellarProbe's answer I was able to visualize the solutions, which suits my needs.
