Was the pattern for the lower half in more than one piece so you can remove say a central part and then the outer two can move inwards then up and out.
Others might go lost PLA route.
Looks like you have the makings of a portable engine though the cylinder would be at the wrong end for that.
Colour of the vents make it look like bronze to me.
Edited By JasonB on 15/08/2023 16:15:08