Accepted Solutions
...after searching the forums and seeing the difficulty that people are having, I wasn't convinced....
The "problem" posts I see most are those using non-Adaptec SCSI cards and / or non parallel SCSI drives. The most recent posts I've seen are for SATA or SAS tape drives. Basically trying to use "new" tape drives rather than reusing "old" tape drives.
Quick is the primary concern here. Money is available, it just can't be a rediculous sum as this is monstly going to be throw away by next year (else I'd just go straight for an iSCSI tape library).
Then I'd recommend the SCSI card since it would be cheaper than a bridge. Or if you have an existing workstation that you can re-task to host your tape drive for a while until you get the rest of your new backup equipment. Used & refurb workstations can be had for well under $500 and often as low as $200 and would be more than powerful enough to host a tape drive. Since you can reuse the workstation after you get the new equipment, you could get something more than the bare minimum for this project. That may be a better use of $$$ instead of a iSCSI bridge that you're going to "throw away." 
I don't have any recomendations for a bridge, but perhaps if your VM that is used for backups doesn't need any vMotion, then you could use a supported SCSI card instead. VMware supports Adaptec parallel SCSI card for physical tape drives so your drive fits the requirement. The SCSI card would likely cost less than a iSCSI bridge. (~$250 vs ~$700.) We got a Adaptec 29320LPE card(which is supported for ESX) and installed in a HP ML385 G5 (the AMD version of the ML380.) The VM is Windows 2008 with Backup Exec 12.5 going to a HP 920 LTO3 autoloader. An alternative anyway, if you can't find a compatible iSCSI bridge and may be "simpler" for the short term until you get your other backup in the future.
BTW, we also have a Quantum DXi3500 VTL connected over iSCSI to the same VM. We go to the VTL first, then duplicate to tape for offsite archiving. While I assume your "quick upgrade" is more of a "minimize cost", the VTL for us was the "quick upgrade". We wasted a lot of time trying to get our existing SCSI card to work with ESX and eventually just got the Adaptec card and had the tape drive working straight away. Likely you won't have trouble with an iSCSI bridge, since there's usually not much to config, but if you did have trouble, it would be easier to swallow a $250 error than a $700 error. 
...after searching the forums and seeing the difficulty that people are having, I wasn't convinced....
The "problem" posts I see most are those using non-Adaptec SCSI cards and / or non parallel SCSI drives. The most recent posts I've seen are for SATA or SAS tape drives. Basically trying to use "new" tape drives rather than reusing "old" tape drives.
Quick is the primary concern here. Money is available, it just can't be a rediculous sum as this is monstly going to be throw away by next year (else I'd just go straight for an iSCSI tape library).
Then I'd recommend the SCSI card since it would be cheaper than a bridge. Or if you have an existing workstation that you can re-task to host your tape drive for a while until you get the rest of your new backup equipment. Used & refurb workstations can be had for well under $500 and often as low as $200 and would be more than powerful enough to host a tape drive. Since you can reuse the workstation after you get the new equipment, you could get something more than the bare minimum for this project. That may be a better use of $$$ instead of a iSCSI bridge that you're going to "throw away."