Blue dial watch $500 or less

Good evening,

I have been considering another blue dial watch to add to my collection. I prefer automatic since the only blue watch I currently have is a 36mm Seamaster Quartz.

I'd like to spend $500 or less, and I am open to second hand also.

Size-wise I would like to stay between 36-38mm but above all, I need the lug to lug to be 46mm or less.

I am a fan of the San Martin SN0113w Blue Aqua Terra as well as the Erebus Ascent blue enamel.

Please share some suggestions. Thank you!