I have never seen something like this before!
https://www.google.com/maps/@34.1702292,-118.6033703,3a,15y,115.45h,104.33t/data=!3m8!1e1!3m6!1sB2Oji_SXNe1m8jWTlA9Ufg!2e0!5s20150701T000000!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fcb_client%3Dmaps_sv.tactile%26w%3D900%26h%3D600%26pitch%3D-14.334806946776752%26panoid%3DB2Oji_SXNe1m8jWTlA9Ufg%26yaw%3D115.45247563119204!7i13312!8i6656?entry=ttu&g_ep=EgoyMDI0MTIwNC4wIKXMDSoASAFQAw%3D%3D

Probably a case of whatever they could get their hands on. The old lights were probably damaged all at once or had issues at some point and they had to get new lights ASAP. If you look closer, one of the the lights is a former HPS 325 with high performance FCO optics.

I have seen some FCO high performance optic 325s on Caltrans roads.

I believe these were also wired in series and they tended to piece together whatever for those circuits.

I found a couple of sco m400as on some freeways. Perhaps they lost glareshields?