Ericsson RBS6000 surplus situation

Hello fellow Osmocomers, I just recently came across and watched Harald's ODC 2018 presentation about Ericsson RBS 6000. The part that intrigued me: Harald said in that year that this hardware was available quite inexpensively and plentifully; he said that a DUG10+RUG pair could be had for around 300 EUR in that year. My question to the community: what is the current situation 6 y later? Is there still any above-zero supply of either DUG10+RUG or DUG20+RUS surplus hardware? If a nonzero supply does exist, what is the typical price these days? In that 2018 presentation Harald also mentioned that the successor to DUG20 was DUS31/DUS41, and that those DUS units (which support GSM, WCDMA and LTE all in one box) have integrated SIU02 equivalent instead of native E1 interfaces. Hence question: has anyone in Osmocom cracked the E1-over-IP protocol spoken by SIU02 and its later incarnations, allowing Osmocom CNI to drive the GSM part of DUS31 etc, or is such operation beyond our current community capabilities? There are rumors going around that T-Mobile USA may be shutting down some Ericsson 2G equipment (though I still never got any clear answers as to what equipment it might be, if any), hence I am trying to brush up on my knowledge of this platform. M~