The comparable JBL's are the 306P for similar driver size. I got my pair on a freak sale for US$172 /
PAIR of Adorama.com
If you find the regular price for the 306P to be a little higher than you wish to pay, there is also the highly rated Kali LP-6, they are regularly sold at US$149 each. But I have yet to see a sale for them.
The SMSL M500 DAC is definitely not at the price you're quoting here.
Its this:
https://www.audiosciencereview.com/forum/index.php?threads/smsl-m500-dac-and-hp-amp-review.9606/
Shenzhen Audio quotes a non-sale price of US$399/-. DHL shipping included.
https://shenzhenaudio.com/collectio...z-dsd512-hi-res-audio-dac-headphone-amplifier
They do drop to about US$350 if there is a sale.
Edit Addendum:
To add, if you're willing to pay that kind of money for the S3000pro, I would suggest taking a closer look at their Airpulse A300.
Its their most expensive model and supposedly their most refined from what I have seen off Chinese forum discussions.