how do i get these signed rom? i want to lock my bootloader but cant unless i have signed bootloader

Visit xda developers.

You will find fastboot flashable stock ROM with bootloader and recovery.

Also the fastboot script to relock bootloader.

Doesnt even need searching.

You will see it once you open xda page for g5plus

TENGO UN PROBLEMA SIMILAR QUICE ACTUALIZAR MI MOTO G5 PLUS XT1687 PERO SEME CUESTIÓN EN FASTBOOT FLASH MODE (SEGURO) EH INTENTADO DE TODO PERO NO LOGRO SOLUCIONARLO CON NADA AL FLASHEARLO ME TIRA ESTE ERROR. ALGUIEN POR FAVOR ME AYUDE NO ACCEDE AH LA RECUPERACIÓN NI A NINGUNA OTRA OPCION SIEMPRE REGRESA AL MODO FASTBOOT ADEMAS TIENE EL BOOTLOADER BLOQUEADO Y VENTA OME BLOQUE ALGUIEN ME AYUDE

C:\Users\CASA\Desktop\platform-tools>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: moto-msm8953-C0.8C
(bootloader) product: potter
(bootloader) board: potter
(bootloader) secure: yes
(bootloader) hwrev: P3B
(bootloader) radio: 1
(bootloader) storage-type: emmc
(bootloader) emmc: 64GB SAMSUNG RC14MB RV=08 PV=07 FV=0000000000000007
(bootloader) ram: 4GB SAMSUNG LP3 DIE=8Gb M5=01 M6=05 M7=00 M8=5F
(bootloader) cpu: MSM8953
(bootloader) serialno: ZY224TCR5N
(bootloader) cid: 0x0012
(bootloader) channelid: 0x93
(bootloader) uid: 83AC454600000000000000000000
(bootloader) securestate: oem_locked
(bootloader) iswarrantyvoid: no
(bootloader) max-download-size: 536870912
(bootloader) reason: Fall-through from normal boot mode
(bootloader) imei: 
(bootloader) meid:
(bootloader) date: 02-07-2018
(bootloader) sku: XT1687
(bootloader) battid: SNN5982A
(bootloader) iccid:
(bootloader) cust_md5:
(bootloader) max-sparse-size: 268435456
(bootloader) current-time: "Wed Jul 29 19:53: 4 UTC 1970"
(bootloader) ro.build.fingerprint[0]: motorola/potter_amz/potter:7.0/NPN
(bootloader) ro.build.fingerprint[1]: S25.137-93-14/14:user/release-keys
(bootloader) poweroffalarm: 0
(bootloader) ro.build.version.full[0]: Blur_Version.25.341.14.potter_amz
(bootloader) ro.build.version.full[1]: .amz.en.US
(bootloader) ro.build.version.qcom: LA.UM.5.6.r1-01900-89xx.0
(bootloader) version-baseband: M8953_37.46.07.47.01R POTTER_NA_CUST
(bootloader) kernel.version[0]: Linux version 3.18.31-perf-gf055b2e-0010
(bootloader) kernel.version[1]: 7-gdc6d2c1 (hudsoncm@ilclbld31) (gcc ver
(bootloader) kernel.version[2]: sion 4.9 20150123 (prerelease) (GCC) ) #
(bootloader) kernel.version[3]: 1 SMP PREEMPT Wed May 30 14:17:37 CDT 20
(bootloader) kernel.version[4]: 18
(bootloader) sbl1.git: git=MBM-NG-VC0.8C-0-g22013cf
(bootloader) rpm.git: git=MBM-NG-VC0.C0-1-g202d600
(bootloader) tz.git: git=6c4172f-dirty
(bootloader) devcfg.git: git=6c4172f-dirty
(bootloader) keymaster.git: git=6c4172f-dirty
(bootloader) cmnlib.git: git=6c4172f-dirty
(bootloader) cmnlib64.git: git=6c4172f-dirty
(bootloader) prov.git: git=6c4172f-dirty
(bootloader) aboot.git: git=MBM-NG-VC0.8C-0-gcba6d5d
(bootloader) qe: qe 0/0
(bootloader) frp-state: protected (144)
(bootloader) ro.carrier: amz
all: listed above
Finished. Total time: 0.203s

C:\Users\CASA\Desktop\platform-tools>

QUE ALGUIEN ME AYUDE AH ENCONTRAR UN STOCK PARA MI G5 PLUS XT1687