FMP provides quick and easy tools for just this.
Create a "Value List" (look under menu File>Manage>Value Lists and create a value list for all of your part id's.
Then you can use it in one or both of the following ways.
1) In the definition or your field PartID, use the validate by value list. This allows the user to manually enter the partid but wont accept an invalid one.
2) In the definition or your layout field, change the display of the PartID field from Text to either Drop Down List or Pop Up Menu and base that on the value list. This lets the user pick from an existing set of valid part ids rather than having to type one in.
Hope that helps.