Looking For Extruded Aluminum Part Like This

I need to be able to source this part.  I've tried Google and can't find any Extruded Aluminum parts that come close to this.  I'm hoping someone out there has seen this and knows where I can get more of it.

The part is 20mm x 20mm, 3 slots that are 10mm each.  

Thanks.

Mike

Picture of Looking For Extruded Aluminum Part Like This
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They are for T-slot assembly.
Any industrial supplier should have then in their lists.
But with that 45° angle I don't think it is a standard variation, at least I can't find this in any of my lists.
If you can do without the 45° part and only need the righ angles it is no problem getting them.

grayhairguy1 month ago

Google modular machine frame for similar part systems. This is industrial 'tinker toy' framing system. There are multiple manufacturers.