Scott what year is your Scamp? I have not seen that style of marker lights before. The photo below is more commonly to see on the Scamps - per the Scramp parts website they have been using the type below since the early 80's to present. They sell them for $4. I agree with Darwin though if you need to replace them go with the LED's you will not be sorry.
Go to Walmart and look for these:
Blazer International LED Multi Faceted Marker Light
They come in Yellow or Red and are less than $8.
You will be able to replace the complete unit in just a few minutes.
im looking for 2 amber marker lens like the one pictured its 4"x2" prefer new but 2 nice used would be ok..thanks Attachment 69724
That looks like a Bargman 378, which is now being put out by another manufacturer. (That's the "correct" original for your late-'70's Scamp, BTW). Check the dimensions for the whole light at this link..