Did a little investigating and found the Z80-MBC is still available as a unpopulated board.  Ordered the board from https://www.ebay.com/itm/283494335966

Ordered most of the components from Jameco., found others on Amazon.  The TO-92 2N2907 seemed to be a tricky article to find heris my parts list

C1, C2, C5, C6, C8, C9, C10, C12 8 Capacitor, Disc, D3 P2.5, 0.1uF
C3, C4 2 Capacitor, Disc, D3 P2.5, 22pF
C7, C11 2 Capacitor, Radial, D6.3 L11.2 P2.5, 16V, 100uF
D1 1 LED 3MM, Red
D11 1 LED 3MM, Red
D2 1 LED 3MM, White
D3 1 LED 3MM, White
D4 1 LED 3MM, Green
D5 1 LED 3MM, Blue
D6, D10 2 Diode, D4,  1N4148
D7, D8, D9 3 Diode, D4, 1N5817
J1 1 Pin Header, 0.1", Vertical, Male, 1x4
J2 1 Pin Header, 0.1", Vertical, Male, 1x8
J3 1 Pin Header, 0.1", Vertical, Male, IDC Shrouded, 2x3
J4 1 Header, JST B2B-XH-A, 2pos 2.50mm, Male
J4 1 Connector, JST XH, 2pos 2.50m, Female
J5 1 Pin Header, 0.1", Vertical, Female, 1x6
J6 1 Pin Header, 0.1", Vertical, Female, 1x6
J7 1 Pin Header, 0.1", Vertical, Male, 2x10
Q2, Q1 2 Transistor, TO-92, 2N2907
R1, R7 2 680 ohm 1/4W 5%
R10, R12 2 390 ohm 1/4W 5%
R3, R4, R5, R8, R9, R11, R14, R15, R21 8 10k ohm 1/4W 5%
R13 1 39 ohm 1/4W 5%
R17, R18 2 4k7 ohm 1/4W 5%
R19 1 1k2 ohm 1/4W 5%
R2, R6, R16 3 1k ohm 1/4W 5%
R20 1 330 ohm 1/4W 5%
RN1, RN2 2 Resistor Array SIP9 (1x8 & 1 common), 10k, 1/8w
SW1 1 Microswitch, 4-pin, momentary, 6x6x5mm
SW2 1 Microswitch, 4-pin, momentary, 6x6x5mm
U1 1 74HC00, DIP-14
U2 1 Z84C0008 (CMOS), DIP-40
U3 1 ATMEGA32A-PU, DIP-40
U4 1 TC551001-70, DIP-32
U5 1 MCP23017, DIP-28
Y1 1 Oscillator, 16MHz, HC-49V / HC-49S
Socket  1 DIP-14 (machine or leaf), 0.300"
Socket  2 DIP-40 (machine or leaf) 0.600"
Socket  1 DIP-32 (machine or leaf) 0.600"
Socket  1 DIP-28 (machine or leaf) 0.300"
z.ICSP Adapter 1 6-to-10 icsp adapter
z.Module 1 RTC Module: DS3231 AT24C32 IIC RTC
z.Module 1 SD Module: MicroSD card module SPI