WR1043 V5 U-Boot

By accident I've deleted the second stage U-Boot:

root@OpenWrt:~# cat /proc/cpuinfo | head -2 ; echo ; hexdump -C /dev/mtd1
system type             : Qualcomm Atheros QCA956X ver 1 rev 0
machine                 : TP-LINK TL-WR1043N v5

00000000  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
*
00020000

Does anybody know where to get this U-Boot ?

maybe in firmware update binary?

thx for the hint - I've done a recovery with TP-Link software and done the OpenWRT Installation again.