Replacement pump for a Vertex in280 or do I buy a new skimmer

[RPatsula]

Hello I am looking for replacement pump for a Vertex in280 or do I buy a new skimmer. My current skimmer is starting to have a hard time starting up after it is been off for 15 to 20 minutes. I have modified the skimmer by adding the gate valve to it which helps me to find tune it a lot easier. With that being said I would like to keep the skimmer if I can find the correct replacement pump. Does anyone have any suggestions.
If I do go down the road of buying a new skimmer, should I stick with Vertex line? If so what is a good model. I have 180 gallon mixed reef tank.

Thank you
Rick